The present invention disclosed herein relates to a method of transmitting and receiving data using a Data Plus (DP) formula in a power line.
Generally, power line communication technology can be classified into a contact-type in which high frequency is transmitted to a power line through a power outlet and a noncontact-type using a Current Transformer (CT) concept. The present invention is similar to the noncontact-type in that a typical CT concept is used.
Power Line Communication (PLC) using a typical noncontact-type coupler (see FIG. 13) has a limitation in that when the data frequency is low, a plus (+) portion or a minus (−) portion of data 502a is reduced according to the power phase, making it difficult to commercialize the power line communication. On the contrary, when the data frequency is high, there is a limitation in long-distance transmission and power consumption because a power line 1301 penetrates CT when valid signal data necessary for data reception is added to the power line. Accordingly, applications of power line communication are limited to a ship, and are difficult to distribute to customers
Most PLC methods transmit and receive data by contacting a power line through a power outlet using a high frequency. Since 1920s, many studies on the PLC have been conducted by national research institutes and enterprises.
There are many media reports that research institutes and companies succeeded in commercializing PLC, but the truth is disappointing. PLC modems for the network in a building are being commercialized and released, but the clear criteria of success is that the probability of data transmission/reception success from transformers to consumers only through a power line needs to be more than 99% when 1,000 consumer's homes are randomly sampled from 19 million consumer homes in Korea. Currently, PLC technology is determined to be less than 50% and impossible to commercialize on the basis of the above-mentioned criteria and data from the Korea Electrotechnology Research Institute (KERI) and PLC-related enterprises. The estimate of the present applicant is less than 23%.